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Randomly mixing ferromagnetic (FM) and antiferromagnetic (AFM) elements in high-entropy alloys (HEAs) can create fluctuating local magnetic moments that influence the energetics of point defects. In this study, we employed first-principles calculations to investigate the influence of magnetic properties on vacancy migration energy in Fe49.5Mn29.4Co10.1Cr10.1C0.9, alongside equiatomic NiCoFeCrMn alloy. By examining structures with paramagnetism, ferromagnetism, and no spin polarization, our study reveals significant impacts of magnetic interactions on vacancy migration barriers, potentially altering the sequence of elemental migration energies if overlooked. In Fe49.5Mn29.4Co10.1Cr10.1C0.9, the order of vacancy migration barriers is Co > Fe > Mn > Cr across all magnetic states, suggesting the dominant roles of atomic properties and inherent chemical bonding. Conversely, the NiCoFeCrMn HEA exhibits a pronounced magnetic state-dependent elemental migration energy order, indicating that magnetic interactions significantly influence vacancy migration behavior in this alloy. In addition, while FM elements generally exhibit higher migration barriers, AFM elements display lower barriers in the investigated Cantor alloys, with notable variations between the studied compositions. These findings underscore the critical role of magnetism in accurate migration energy calculations, which is important for studying chemically biased diffusion and radiation-induced segregation in HEAs. [ABSTRACT FROM AUTHOR]

In this study, we present results of a comprehensive computational and experimental study of CoFeVAl and CoFeV0.5Mn0.5Al Heusler alloys. It is shown that while CoFeVAl exhibits a fairly large degree of spin polarization, this material is not half-metallic due to the presence of the vanadium spin-down states at the Fermi level. However, replacing 50% of vanadium with manganese results in a nearly half-metallic transition, largely due to the shift of the Fermi level towards occupied states. Moreover, the half-metallicity of CoFeV0.5Mn0.5Al is rather robust in a wide range of considered mechanical strain and under experimentally observed B2-type atomic disorder, thus making this alloy potentially suitable for practical spintronic applications. Both considered alloys exhibit ferromagnetic alignment at larger lattice constants, aside from a relatively small magnetic moment of vanadium which is anti-aligned with the magnetic moments of Co, Fe and Mn. We have synthesized both CoFeVAl and CoFeV0.5Mn0.5Al alloys in cubic structure with some structural disorder using arc melting and annealing. The structural and magnetic properties of the synthesized CoFeV0.5Mn0.5Al alloy are in good agreement with the theoretical calculations but vary slightly from the parent compound. [ABSTRACT FROM AUTHOR]

We investigate the magnetic properties of La2/3Sr1/3MnO3 (LSMO) membranes released from an SrTiO3 (STO) substrate by selectively etching an Sr4Al2O7 sacrificial buffer layer. The magnetic moment and Curie temperatures (TC) of the released LSMO membranes improve significantly over their substrate-bound counterparts. We attribute these enhancements to suppressing strain and oxygen octahedral rotations that are present in substrate-bound films. Moreover, comparing the magnetic hysteresis loops obtained with magnetic fields applied along several crystallographic orientations demonstrates enhanced (weakened) perpendicular (in-plane) magnetic anisotropy in the released LSMO membranes. Our results contribute to potential applications of released LSMO membranes toward flexible spintronics devices, where high spin polarization and TC are desired. [ABSTRACT FROM AUTHOR]

We present detailed investigations of the magnetic properties of Pt/CoFeB/MgO layers as studied using the angle-resolved spin-torque ferromagnetic resonance method. Although the measurements provide reasonable magnetic parameters, we obtain an unusual value in the interfacial spin transparency if spin-pumping is assumed to be the dominant source for enhancing magnetic damping (αeff) in the nanometer thickness regime. However, the thickness dependence of the Landé g-factor (geff) for CoFeB indicates that the interfacial spin–orbit coupling plays a role in determining αeff. In addition, the azimuthal asymmetry in the magnetic system may not be related to the possibility of generating unconventional spin polarization. The results in this work are expected to aid in understanding various magnetic properties and current-induced spin-torques in a heavy-metal/ferromagnet bilayer. [ABSTRACT FROM AUTHOR]

Buckybowls have been drawing considerable attention because of their unique electronic structures and physical properties. However, few studies have investigated their magnetic properties. In the present investigation on organic molecular magnets, flatly conjugated structures are generally used as couplers. However, there are few reports on the use of curvature couplers for constructing molecular magnets. In this study, a series of dual nitroxide diradical molecular magnets are designed with triphenylene and its edge-modified derivatives (by the –CH2–, –NH–, or –O– edge-bridging groups) as the couplers, and their magnetic coupling properties are studied at the density functional theory level. It is interesting to note that all the designed diradicals exhibit antiferromagnetic (AFM) properties and the curvature of the coupler can considerably enhance their magnetic coupling strength. The curvature of the coupler can reduce its aromaticity and increase the spin polarization of nitroxide groups, thereby enhancing the AFM. The electronic properties of the bridging groups (such as –NH–, –O–) can further enhance the AFM coupling strength of the diradicals by manipulating the π electron distribution on the coupler, especially with the assistance of intramolecular H-bonds for the –NH– edge-bridge. This study provides insights into the magnetic modulation of molecular magnets through the curvature of couplers and also offers valuable information on constructing curved molecular magnets. [ABSTRACT FROM AUTHOR]

The effects of vacancy defects and noble metals (NM = Rh, Ru, Pd, Ag) on the structural stability, electronic structure, and magnetic properties of arsenene were investigated using a first‐principles study. Vacancy defects have a great influence on both the magnetic properties and the band gap of arsenene. With the decrease in defect concentration, the magnetic moment of the vacancy defect system can be increased, and the bandgap transition from metal‐direct–indirect can be realized. After NM adsorption of vacancy defect arsenene, we considered three defect concentrations. It was indicated that there was a large adsorption energy between NM and vacancy‐defective arsenene, indicating that the adsorption system was relatively stable while the change in defect concentration did not have a significant effect on charge transfer. Except for the Ag adsorption system, the defect concentration can effectively modulate the band gap of the adsorption system and make it exhibit various electronic structures, such as semiconductors and metals. In terms of magnetic properties, not all NM atoms can induce arsenene to appear magnetic. Except for the Ag adsorption system, the defect concentration can make the adsorption system exhibit a variety of magnetic properties. It can induce the magnetic state of vacancy‐defective arsenenes or lead to the disappearance of magnetism. The spin polarization of the adsorption system mainly originates from the NM atoms or As atoms around the vacancies. [ABSTRACT FROM AUTHOR]

A subclass of ternary intermetallic known as Heusler compounds is being employed in the steel industry to increase material strength. This study examines the structural, electrical, optical, and magnetic properties of Co2VZ (Z=Al, Bi, Ge, Si) compounds using two different methods. First is full potential linearized augmented plane wave (FP-LAPW) method by WIEN2k and second is pseudo potential method by Atomic Tool Kit-Virtual Nano-Lab. The equivalent energy gaps in the minority-spin of Co2VZ (Z= Al, Bi, Ga, Ge) with WIEN2k code, which displays 100% spin polarization, are 0.703, 0.384, 0.186, and 0.67 eV near to the Fermi level. Furthermore, it is discovered that these compounds are absolutely half-metallic ferromagnetic (HMF). With the exception of Co2VBi, which exhibits metallic properties, the aforementioned compounds exhibit 0.525, 0.0, 0.553, and 0.786 eV band gaps in the ATK-VNL code and indicate 100% spin polarization. The magnetic moments of the compounds Co2VZ (Z= Al, Bi, Ga, Ge) are found to be 2.976, 4.003, 1.989, and 3.001 µB, respectively, in the WIEN2k code. The relative magnetic moments of the aforementioned compounds are also 1.991, 3.947, 1.999, and 2.997 µB, according to the ATK-VNL code. [ABSTRACT FROM AUTHOR]

Density functional theory in the framework of generalized gradient approximation (GGA) of Perdew–Burke–Ernzerhof to investigate the effects of some selected transition metal (TM) and rare‐earth metal (RE) dopants on the electronic and magnetic properties of a 2D molybdenum disulfide (MoS2) monolayer is reported. The results demonstrate that it is energetically stable to incorporate Ni and Cu in MoS2 structure under Mo‐rich conditions. The pristine MoS2 monolayer has a calculated direct bandgap of 1.70 eV and experiences significant reduction in the gap due to the defects. There is observed induced magnetic behavior due to the tight binding effect originating from the localized dopants and the nearest‐neighbor Mo atoms, with magnetic moments ranging between 0.82 and 3.00 μB. Some of the dopants result in 100%$$ spin polarization which is useful for engineering spin filter devices on magnetic MoS2 nanostructures. [ABSTRACT FROM AUTHOR]

Using the first-principles calculations based on density functional theory (DFT) within the generalized gradient approximation (GGA), Ti2RuAl full-Heusler compound is studied. The electronic structure, magnetic, and optical properties of Ti2-based full Heusler compound Ti2RuAl are calculated and analyzed using the Wien2k package. The CuHg2Ti-type structure is found to be more favorable than the AlCu2Mn-type structure for this compound. The Ti2RuAl Heusler compound exhibits a ferrimagnetic half-metallic behavior with the total magnetic moment of 1 µB at the equilibrium lattice constant 6.24 Å. The total magnetic moment of Ti2RuAl is in agreement with the Slater-Pauling rule mtot = ztot–18 and hence has integral magnetic moments which is due to 100% spin polarization at Fermi energy. Ti2RuAl has an energy gap in the spin-down channel of 0.229 eV. This compound keeps a 100% of spin polarization for lattice constant change in the range of 5.8–6.5 Å. The Curie temperature of Ti2RuAl is estimated to be 451 K using the mean field approximation (MFA). In addition, optical properties like dielectric function, reflectivity, energy loss function, absorption coefficient, and optical conductivity are calculated. [ABSTRACT FROM AUTHOR]

A systematic structure and property investigation of MnGen− (n = 3–14) was conducted by means of density functional theory coupled with mass-selected anion photoelectron spectroscopy. This combined theoretical and experimental study allows global minimum and coexistence structures to be identified. It is found that the pentagonal bipyramid shape is the basic framework for the nascent growth process of MnGen− (n = 3–10), and from n = 10, the endohedral structures can be found. For n = 12, the anion MnGe12− cluster probably includes two isomers: a major isomer with a puckered hexagonal prism geometry and a minor isomer with a distorted icosahedron geometry. Specifically, the puckered hexagonal prism isomer follows the Wade–Mingos rules and can be suggested as a new kind of superatom with the magnetic property. Furthermore, the results of adaptive natural density partitioning and deformation density analyses suggest a polar covalent interaction between Ge and Mn for endohedral clusters of MnGe12−. The spin density and natural population analysis indicate that MnGen− clusters have high magnetic moments localized on Mn. The density of states diagram visually shows the significant spin polarization for endohedral structures and reveals the weak interaction between the Ge 4p orbital and the 4s, 3d orbitals of Mn. [ABSTRACT FROM AUTHOR]

Defects play significant roles in spin-current-related physical processes in intrinsic ferromagnetic semiconductors (FMSs), which are great promise for spintronics applications. However, current defect calculation methods cannot be used to investigate charged defects in FMSs due to the spin polarization of both the charged defect states and ionized carriers, which is not well treated in current defect calculation methods. In order to solve this problem, we propose a spin-distinguishable charge correction (SDCC) method that uses spin-polarized band edge charge density instead of spin-unpolarized uniform background charge density as the compensating charge for charged defects. We apply our method to study the defect properties of CrI3 monolayer and find it can be doped n-type under the Cr-rich growth condition but difficult to be doped p-type. The SDCC method proposed here is generally suitable for all FMSs, which will be useful for the studies of defect properties of magnetic semiconductors. [ABSTRACT FROM AUTHOR]

Here, we report the experimental investigations on magnetic (spin polarization and exchange bias) and transport (spin-flip and spin-flop) properties of Co2FeSi Heusler compound at cryo temperature and high magnetic field. The spin cluster characteristic of the material is revealed by the M[T] curve of the ZFC, FC, and FW cycles. This can exhibit spin polarization behavior of anti-ferromagnetism (AFM) at 30–70 K. Furthermore, at a critical field of 0.2 T, AFM transforms into ferromagnetic (FM) and on further increasing the magnetic field, the spin polarization region becomes linear due to perseverance of FM behavior. The isothermal magnetization [M(H)] are also evaluated at different temperatures and AFM to FM transition has been observed at various applied magnetic fields. These magnetic measurements are used to determine exchange bias [EB] parameters such as HE, HC, and Mr both at low and room temperature. The resistivity [ρ(T)] has been measured at 0 and 5 T field, which explain the increasing trend of metallic nature at cooling cycle and also provides a clear evidence of magnonic, phononic resistivity and spin-flip scattering. [ABSTRACT FROM AUTHOR]

Two-dimensional ferromagnetic (FM) half-metals are highly desirable for the development of multifunctional spintronic nano-devices due to their 100% spin polarization and possible interesting single-spin electronic states. Herein, using first-principles calculations based on density functional theory (DFT) with the Perdew–Burke–Ernzerhof (PBE) functional, we demonstrate that the MnNCl monolayer is a promising FM half-metal for spintronics. Specifically, we systematically investigated its mechanical, magnetic, and electronic properties. The results reveal that the MnNCl monolayer has superb mechanic, dynamic, and thermal (ab initio molecular dynamics (AIMD) simulation at 900 K) stability. More importantly, its intrinsic FM ground state has a large magnetic moment (6.16 μB), a large magnet anisotropy energy (184.5 μeV), an ultra-high Curie temperature (952 K), and a wide direct band gap (3.10 eV) in the spin-down channel. Furthermore, by applying biaxial strain, the MnNCl monolayer can still maintain its half-metallic properties and shows an enhancement of magnetic properties. These findings establish a promising new two-dimensional (2D) magnetic half-metal material, which should expand the library of 2D magnetic materials. [ABSTRACT FROM AUTHOR]

In this work, the electronic and magnetic features of the Sc2MnSi bulk, surfaces, and the interface with the semiconductor CdTe (111) were thoroughly researched using the first-principles calculations. The Sc2MnSi alloy with equilibrium lattice constant of 6.34 Å shows half-metallic (HM) property. This alloy exhibits an energy gap and a HM gap of 0.54 and 0.12 eV, respectively. The density of states results confirm the existence of the half-metallicity property for the Sc2MnSi component at SiSc(2)-(001), Sc(2)-, and Si-(111) surfaces while this property is not revealed at Sc(1)-, Mn-terminated (111), Sc(1)Mn-terminated (001), and Sc2MnSi (110) surfaces for the same component. In addition, in the case of Sc2MnSi/CdTe interface, it is noted that Cd-Si connection does not reveal the half-metallicity feature, while the Si-Te shape exhibits a 100% spin polarization, thus preserving the half-metallicity. Furthermore, the Si-Te shape is more stable than the others, according to the interfacial adhesion energy. [ABSTRACT FROM AUTHOR]

ZnCoO:H and ZnCoAlO:H films were synthesized by radio frequency magnetron sputtering in a (1 − x)Ar + xH2 mixed atmosphere with x = 0.2–0.5. The films contain different amounts of metallic Co particles (from 7.6% and higher) ~4–7 nm in size. The magnetic and magneto-optical (MO) behavior of the films was analyzed in combination with their structural data. The samples exhibit high values of magnetization (up to 377 emu/cm3) and MO response at room temperature. Two situations are considered: (1) the film magnetism is associated only with isolated metal particles and (2) magnetism is present both in the oxide matrix and in metal inclusions. It has been established that the formation mechanism of the magnetic structure of ZnO:Co2+ is due to the spin-polarized conduction electrons of metal particles and zinc vacancies. It was also found that in the presence of two magnetic components in the films, these components are exchange-coupled. In this case, the exchange coupling generates a high spin polarization of the films. The spin-dependent transport properties of the samples have been studied. A high value of the negative magnetoresistance of the films at room temperature (~4%) was found. This behavior was explained in terms of the giant magnetoresistance model. Thus, the ZnCoO:H and ZnCoAlO:H films with high spin polarization can be considered as sources of spin injection. [ABSTRACT FROM AUTHOR]

Recently, 2D Janus structures containing oxygen have attracted great attention from researchers. Herein, the ZrXO (X = S and Se) Janus monolayers are investigated using first‐principles calculations based on the projector augmented wave (PAW). ZrSO and ZrSeO single layers are dynamically and thermally stable, and exhibit the indirect gap semiconductor character with a bandgap of 1.91(2.88) and 1.09 (1.88) eV, respectively, as determined by the standard PBE (hybrid HSE06) functional. The charge transfer process from Zr atom to IVA‐atoms is confirmed by means of the charge density difference and Bader population analysis. Studied 2D materials exhibit good absorption in a wide energy range from visible to ultraviolet regimes with larger absorption coefficient reaching to the order of 105 cm−1. To magnetize the ZrXO monolayers for possible spintronic applications, fluorine (F) and chlorine (Cl) doping is proposed. Significant magnetic properties with total magnetic moments ≈1 μB are obtained. Besides, high spin polarization around the Fermi level is also induced as a result of the feature‐rich half‐metallic or magnetic semiconductor natures. Results presented herein introduce ZrSO and ZrSeO monolayers as prospective 2D materials to be applied high‐performance nano optoelectronic and spintronic devices. [ABSTRACT FROM AUTHOR]

We have carried out joint theoretical and experimental investigations of three Heusler compounds CoMoFeAl, CoMo0.5Fe1.5Al, and Co1.5Mo0.5FeAl. Our first-principle calculations show that all three compounds show either ferro- or ferrimagnetic order with CoMoFeAl and CoMo0.5Fe1.5Al exhibiting high spin polarization of almost 80%. The investigated samples were prepared using arc melting and high vacuum annealing. All the samples show cubic crystal structure with disorder. The parent compound CoMoFeAl shows a small saturation magnetization of 12 emu/g, and a Curie temperature of 440 K. The other two compounds, namely, Co1.5Mo0.5FeAl and CoMo0.5Fe1.5Al, show much higher saturation magnetizations of 62 emu/g and 59 emu/g, and substantially higher Curie temperatures of 950 K and 780 K, respectively. [ABSTRACT FROM AUTHOR]

The electronic and magnetic properties of graphene/MoS2 heterostructures intercalated with 3d transition metal (TM) atoms at different concentrations have been systematically investigated by first principles calculations. The results showed that all the studied systems are thermodynamically stable with large binding energies of about 3.72 eV–6.86 eV. Interestingly, all the TM-intercalated graphene/MoS2 heterostructures are ferromagnetic and their total magnetic moments increase with TM concentration. Furthermore, TM concentration-dependent spin polarization is obtained for the graphene layer and MoS2 layer due to the charge transfer between TM atoms and the layers. A significant band gap is opened for graphene in these TM-intercalated graphene/MoS2 heterostructures (around 0.094 eV–0.37 eV). With the TM concentration increasing, the band gap of graphene is reduced due to the enhanced spin polarization of graphene. Our study suggests a research direction for the manipulation of the properties of 2D materials through control of the intercalation concentration of TM atoms. [ABSTRACT FROM AUTHOR]

We have carried out a combined theoretical and experimental investigation of both stoichiometric and nonstoichiometric CoFeVGe alloys. In particular, we have investigated CoFeVGe, Co1.25Fe0.75VGe, Co0.75Fe1.25VGe, and CoFe0.75VGe bulk alloys. Our first principles calculations suggest that all four alloys show ferromagnetic order, where CoFeVGe, Co1.25Fe0.75VGe, and Co0.75Fe1.25VGe are highly spin polarized with spin polarization values of over 80%. However, the spin polarization value of CoFe0.75VGe is only about 60%. We have synthesized all four samples using arc melting and high-vacuum annealing at 600 °C for 48 hours. The room temperature x-ray diffraction of these samples exhibits a cubic crystal structure with disorder. All the samples show single magnetic transitions at their Curie temperatures, where the Curie temperature and high field (3T) magnetization are 288 K and 42 emu/g; 305 K and 1.5 emu/g; 238 K and 39 emu/g; and 306 K and 35 emu/g for CoFeVGe, Co1.25Fe0.75VGe, Co0.75Fe1.25VGe, and CoFe0.75VGe, respectively. [ABSTRACT FROM AUTHOR]

The structural parameters, exchange splittings, half-metallic property, electronic features and magnetic performances of Ba1−xCrxS materials were determined by utilizing the computational methods of density functional theory. The localized magnetic spins in the Ba1−xCrxS result from the effect of the hole carriers caused by the d shells of Cr atom, hybridizing with p levels of S atom. The ferromagnetism is mostly endorsed by the exchange splitting owing to its large contribution than that of the crystal field. The Ba1−xCrxS (x = 0.25), Ba1−xCrxS (x = 0.5)and Ba1−xCrxS (x = 0.75) materials have half-metallic characteristic with ferromagnetic state, where their electronic structures demonstrate spin polarizations of 100% with half-gaps of 0.815, 0.912 and 0.72 eV, respectively. Therefore, Ba1−xCrxS systems have better magneto-electronic performances, making them appropriate half-metallic materials for spin-injection applications for spintronics. [ABSTRACT FROM AUTHOR]

In our previous works [J. Phys. Chem. Solids 163 (2022) 110600], the CrLaCoAl alloy had been predicted to be half-metallic ferrimagnet with high Curie temperature, and it met the dynamic, mechanical and thermal stabilities. Furthermore, a smaller convex hull indicated that it was likely to be prepared in experiment. However, the half-metallicity of CrLaCoAl alloy is possible to be destroyed by defect. Therefore, it is necessary to study the stability, electronic and magnetic properties of defective CrLaCoAl. Results show that the formation energies of the Cr–La, Co–Al swap and Al(Cr), Co(La) antisite are negative, indicating that they are likely to be formed in the process of crystal growth. Among them, the formation energy of the Al(Cr) antisite is the lowest in defects, and the spin polarization is as high as 93.72%. In addition, the spin polarization of all antisites is over 60% except for the Cr(Al), La(Cr) and La(Al) antisite. High spin polarization in defect is favorable in spintronic application. [ABSTRACT FROM AUTHOR]

The crystal structure and magnetic properties of Fe4BO7 and Mn4BO7 tetraborates have been studied within DFT-GGA. The tetraborates can be found in several possible structural modifications. Three of them, namely, (α-ZnB4O7), (β-ZnB4O7 structure type), and (γ-NiB4O7 structure type) have been considered here. The possible magnetic orderings in three structure types are described within group-theoretical analysis. The following DFT calculations allow finding the lowest energy magnetic structure for Fe4BO7 and Mn4BO7 in three structure types. The total energies of tetraborates in three structure types have been compared with and without taking into account the spin polarization. It has been found that Mn4BO7 and Fe4BO7 in the non-spin-polarized case have the α-ZnB4O7 and γ-NiB4O7 structure types as the lowest energy structure, respectively. However, when the magnetic structure is taken into account, the antiferromagnetic α-ZnB4O7 phase becomes the ground state for both tetraborates. The pressure dependence of the enthalpy of Fe4BO7 and Mn4BO7 tetraborates has been studied. It has been found that the applied pressure results in the appearance of the β-ZnB4O7 structure type as the lowest energy structure under pressure. [ABSTRACT FROM AUTHOR]

Electrical control of spin transport at single molecule level is highly desired for molecular nanospintronics. By exploiting magnetic bistability of spin crossover complexes, the magnitude of spin polarization can be modulated. However, efficiently controlling the direction of spin polarization at single molecule level is still challenging. Here, we propose a general method to flip the transport electron spin simply by electrical gating in single molecule devices based on bipolar magnetic molecules (BMMs), of which the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) come from different spin channels. Thus, when the device's Fermi level is reversibly adjusted approaching either HOMO or LUMO by changing the polarity of the applied voltage gate, a 100 % spin polarized current with switchable spin direction is achievable. The proposed method is verified by the calculated electronic and transport properties of 9 potential transition metal coordination BMMs. [ABSTRACT FROM AUTHOR]

Electrical control of spin transport at single molecule level is highly desired for molecular nanospintronics. By exploiting magnetic bistability of spin crossover complexes, the magnitude of spin polarization can be modulated. However, efficiently controlling the direction of spin polarization at single molecule level is still challenging. Here, we propose a general method to flip the transport electron spin simply by electrical gating in single molecule devices based on bipolar magnetic molecules (BMMs), of which the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) come from different spin channels. Thus, when the device's Fermi level is reversibly adjusted approaching either HOMO or LUMO by changing the polarity of the applied voltage gate, a 100 % spin polarized current with switchable spin direction is achievable. The proposed method is verified by the calculated electronic and transport properties of 9 potential transition metal coordination BMMs. [ABSTRACT FROM AUTHOR]

First-principle calculations were used to simulate the changes in magnetic parameters and interatomic charge density in the crystal structure of yttrium iron garnet (YIG) caused by Ca–Sn co-doping. The simulation results illustrate that Ca and Sn have no spin polarization in the crystal, and the charge density among ions tends to increase with doping concentration. A solid-state reaction method was employed to prepare YIG with varying concentrations of Ca–Sn co-doping. The saturation magnetization ($4\pi M_{s}$) of the material shows an initial increase and then decrease as the number of doping increases. This phenomenon of increment in $4\pi M_{s}$ at first could be accounted for the increase of the net magnetic moment of material. The reduction in $4\pi M_{s}$ could be interpreted as the content of Fe3+ ($5~\mu \text{B}$) decreases, while the Fe2+ ($4~\mu \text{B}$) in the material becomes the primary portion when the concentration of doping exceeds 0.10. [ABSTRACT FROM AUTHOR]

Magnetic tunnel junctions are the core component of spintronic devices, and good magnetic tunnel junctions require high tunnel resistance, which is determined by the spin polarization of the thin films of ferromagnetic layers that make up their structure. Therefore, the design of ferromagnetic films with high spin polarization is a current research hotspot in this field. In the current study, we taken the half-metallic CrYCoAl as an object, and studied the influence of surface effect on the half-metallic behavior. Especially, we constructed the CrYCoAl (100), (110), and (111) surfaces to study their stability, electronic and magnetic properties. Results show that the YY and YAl (100) surfaces, and Co (111) surface retain the half-metallic behavior and structural stability of bulk, which provide a basis for CrYCoAl application as a thin films in magnetic tunnel junctions thus, they are likely to be used in the spintronic devices. • Stability of CrYCoAl (100), (110) and (111) surfaces are estimated by their phase diagrams. • Atomic relaxation and surface roughness are discussed. • Electronic and magnetic properties of CrYCoAl (100), (110) and (111) surfaces are studied. • The YAl and YY (100), and Co (111) termination surfaces maintain the half-metallic nature of bulk CrYCoAl. [ABSTRACT FROM AUTHOR]

• Highly ordered L2 1 type heusler alloy film on cu substrate. • Near stoichiometric Co 2 FeSn films by electrodeposition. • High magnetic moment, high T C and high effective anisotropy films. • Co 2 FeSn films (320 nm −1400 nm thick) with high crystalline order. • Minority band gap close (∼0.05 eV) to fermi level. Co 2 FeSn films have been electrochemically deposited on polycrystalline Cu substrates in potentiostatic mode. Processed films with thicknesses of 320 nm, 780 nm, and 1400 nm exhibited highly ordered L2 1 type crystal structure with saturation magnetizations of 1023.38 kA/m (5.08 ± 0.04 μ B /f.u.), 1035.31 kA/m (5.14 ± 0.04 μ B /f.u.) and 1044.34 kA/m (5.18 ± 0.04 μ B /f.u.) at 5 K and 965.00 kA/m (4.79 ± 0.04 μ B /f.u.), 967.75 kA/m (4.81 ± 0.04 μ B /f.u.), and 1003.52 kA/m (4.97 ± 0.04 μ B /f.u.) at 300 K, respectively. The soft ferromagnetic films possess coercivity of ∼ 15.92 kA/m (200 Oe) with a high effective anisotropy constant of ∼ 105 J/m3. Thermo-magnetization measurements yielded high Curie temperatures of 995 K, 1005 K, and 1123 K for films of thicknesses 320 nm, 780 nm, and 1400 nm, respectively. Tailoring the thickness from 320 to 1400 nm could be achieved by merely varying the electrodeposition time without appreciable departure from chemical stoichiometry or compromise in crystalline order or magnetic properties. This establishes a methodology to prepare high quality L2 1 ordered Co 2 FeSn films with a few hundred nanometers thickness by electrodeposition. Electrodeposited Co 2 FeSn films with high magnetic moment, high K e f f value, and high Curie temperature are potential candidates for fabricating nanomagnetic devices. [ABSTRACT FROM AUTHOR]

Spin-Polarized optical parameters for Sr 2 UFeO 6 double perovskite. [Display omitted] • The Sr 2 UFeO 6 is half-metallic having indirect energy band gaps. • The Sr 2 UFeO 6 to be anti-ferromagnetic with a major contribution from Fe+3. • The Sr 2 UNiO 6 , as ferromagnetic in nature with a major contribution from Ni+6. • The peaks in ε 2 ω are linked to various inter-band transitions. • These double perovskites show substantial absorption in UV region. The electronic, and magneto-optical properties of Sr 2 UXO 6 (X = Fe, & Ni) double perovskite materials, in the monoclinic structure, were calculated employing the full-potential Linearized augmented plane wave (FP-LAPW) approach based on the density functional theory (DFT). The results reveal that Sr 2 UFeO 6 is half-metallic and anti-ferromagnetic, whereas Sr 2 UNiO 6 is semiconducting and ferromagnetic. The spin-polarized linear optical features, including the dielectric functions, absorption coefficients, energy loss functions, reflectivity coefficient, and refractive indexes, have been calculated and analyzed in the energy range of 0–14 eV. The study reveals that both materials exhibit transmission at low energies, making them promising candidates for optoelectronic applications. Moreover, the presence of distinct absorption and reflectivity peaks suggests potential applications in tunable optical devices and sensors. The dispersion characteristics of the refractive index open up new possibilities for developing novel photonic materials. [ABSTRACT FROM AUTHOR]

First principles calculations are performed to investigate the thermodynamical stability, dynamical, mechanical, electronic and magnetic properties of CrTiCoZ (Z = Al/Si) novel quaternary Heusler alloys. A Y-type III atomic configuration is found to be the most stable structure for both compounds. The lattice constant values obtained using GGA-PBE approach are 5.9368 Å and 5.7853 Å for CrTiCoAl and CrTiCoSi, respectively. Using the value of elastic moduli for both the compounds, the computed Pugh's ratio value is 2.5 and 2.7 for CrTiCoAl and CrTiCoSi, respectively, which is higher than 1.75, indicating both the compounds are ductile in nature. The melting temperatures of both compounds are as high as 2142 K and 2420 K for CrTiCoAl and CrTiCoSi, respectively. The electronic structure calculations, using the GGA-PBE approach, show a half metallic behavior of CrTiCoAl. The spin-down channel exhibits a direct band gap of 0.15 eV, whereas the spin-up channel is metallic, making CrTiCoAl a half metallic ferromagnet with 100% spin polarization and an appreciable magnetic moment of −2 μB. However, CrTiCoSi is found to be semi-metallic in the spin-down channel and metallic in the spin-up channel, which leads to a spin polarization of 99.7% with a non-integer magnetic moment of −0.99 μB. The Curie temperature of CrTiCoAl is well above the room temperature (385 K), whereas that of CrTiCoSi is below the room temperature (203 K). Thus, CrTiCoAl is found to be more promising than CrTiCoSi as a spin injector in spintronic devices. [ABSTRACT FROM AUTHOR]

In this paper, the first principle method based on density functional theory is used to calculate the electronic structure, magnetic moment, and charge density and differential charge density of the thin film growth system whose epitaxial relation is CoSi (001)//MgO (001). The results show that when the lattice constants a and b of CoSi crystal are set as 0 .84224 nm and C =0.28135 nm, the energy of the system is the lowest and the most stable equilibrium state is reached. It can be seen from the spin polarization band diagram, total electron state density and fractal density that the guide band bottom and valence band top of the CoSi epitaxial film overlap significantly, thus showing the gold property and producing obvious spin cracking phenomenon near the Fermi level. The valence band top is mainly composed of THE 3d7 state electrons of Co, while the conduction band bottom is mainly composed of the 3p state electrons of Si. At the same time, it can be seen from the state density that the phenomenon of pseudo energy gap is generated. The Co-3d state electrons not only mainly contribute to the state density, but also are speculated to be the main factor for the magnetic generation of the film. According to the calculated Mulliken charge and charge density, electrons are transferred from Si to Co, and Co ACTS as the electron acceptor, forming an anti-bonding state between Co and Si, and forming a covalent bond structure between Co and Si. The CoSi under this epitaxial relationship is ferromagnetic and the total magnetic moment is 0.52 μB. [ABSTRACT FROM AUTHOR]

In order to make GaN nanowires better used in the field of spin‐polarized electron sources, the structure and properties of transition metal (Cr, Mn, Fe, Co, and Ni) particles doped nanowires are studied through first principles. The research results show that transition metal (TM) particles are more likely to be doped on the outermost surface of GaN nanowires. The work function of Cr‐doped GaN nanowires has the largest decrease, which is 2.06 eV. For TM‐doped nanowires, magnetic moments are induced, which are mainly derived from the polarization of 3d electrons of TM atoms and 2p electrons of N atoms. Mn‐doped GaN nanowires with 100% spin polarization characteristics seem to be good candidates for spin‐polarized electron source photocathode applications. [ABSTRACT FROM AUTHOR]

The structural, electronic, and magnetic properties of pure and Ti doped w-AlN were investigated using density functional theory with motivation to explore the properties of TiAl-VN complex in the matrix. A substitutional Ti dopant with cationic Al atom at nearest neighbor lattice site of VN was incorporated to form TiAl-VN complex in AlN. The electronic properties of the material revealed that TiAl-VN complex is energetically favorable in AlN and possessed a stable spin-triplet 3A2 ground state and doubly degenerate 3E excited state. A charge transfer from nitrogen vacancy towards Ti dopant was observed which was responsible to increase spin polarization in the electronic structure of AlN host material. Two intermediate band peaks due to hybridized Ti-3d states with N-2p states were seen in the forbidden region narrowing the bandgap of AlN. A local magnetic moment of 2.068 µB was found for the TiAl-VN complex in AlN that was reduced to 0.664 µB on doubling TiAl-VN complex. Hence, TiAl-VN complexes in AlN prefer to couple antiferromagnetically, switched by superexchange interactions between them. Our results show that TiAl-VN complex in AlN may be a robust candidate for applications in optoelectronics and antiferromagnetic spintronics devices. [ABSTRACT FROM AUTHOR]

Strain-mediated magnetism in 2D materials and dilute magnetic semiconductors hold multi-functional applications for future nano-electronics. Herein, First principles calculations are employed to study the influence of biaxial strain on the magnetic properties of Co-doped monolayer W S 2 . The non-magnetic W S 2 shows ferromagnetic signature upon Co doping due to spin polarization, which is further improved at low compressive (-2 %) and tensile (+2 %) strains. From the PDOS and spin density analysis, the opposite magnetic ordering is found to be favourable under the application of compressive and tensile strains. The double exchange interaction and p-d hybridization mechanisms make Co-doped W S 2 a potential host for magnetism. More importantly, the competition between exchange and crystal field splittings, i.e. ( Δ ex > Δ cfs ), of the Co-atom play pivotal roles in deciding the values of the magnetic moments under applied strain. Micromagnetic simulation reveals, the ferromagnetic behavior calculated from DFT exhibits low-field magnetic reversal (190 Oe). Moreover, the spins of Co-doped W S 2 are slightly tilted from the easy axis orientations showing slanted ferromagnetic hysteresis loop. The ferromagnetic nature of Co-doped W S 2 suppresses beyond ± 2 % strain, which is reflected in terms of decrease in the coercivity in the micromagnetic simulation. The understanding of low-field magnetic reversal and spin orientations in Co-doped W S 2 may pave the way for next-generation spintronics and straintronics applications. [ABSTRACT FROM AUTHOR]

In spintronics and magnonics, materials that offer tunable perpendicular magnetic anisotropy (PMA) along with low Gilbert damping and high spin polarization are particularly important. Therefore, a lot of studies are performed on Co/Ni films, that aim at satisfying all these requirements. Moreover, the Dzyaloshinskii−Moriya interaction is induced in them by surrounding the magnetic layers with heavy metal or oxide layers. For this reason, the study of the oxidation of Co/Ni is of particular interest. Therefore, the magnetic properties of Co/Ni bilayers after plasma oxidation (PO) are investigated. It is shown that the magnetic anisotropy of these bilayers can be tuned, not only by the thicknesses of Co and Ni layers, but also by oxidation time varied in the range between 15 and 220 s. After PO, the effective thickness of ferromagnetic Ni is reduced, but it does not oxidize more than ≈2 nm, even for longer oxidation. However, the contribution to PMA increases for the entire range of oxidation times. This indicates that the thickness reduction of the Ni layer is not the only source of PMA enhancement. This additional contribution is attributed to the exchange bias coupling between the ferromagnetic (Co/Ni) and the antiferromagnetic NiO layers. [ABSTRACT FROM AUTHOR]

The first-principle calculations of density functional theory were used to study the structural, electronic, magnetic, mechanic, and half-metallic behavior of Y2MnZ (Z = Al, Ga, In) within the spin generalized gradient approximation. These compounds can be experimentally synthesized due to their negative values of the calculated formation energies. Our calculations indicate that they are more stable in Cu2MnAl-type structure. The Hg2CuTi-type structure displays half-metallic characteristic with 100% spin polarization at the Fermi level. The value of calculated magnetic moment has an integer value of 2μB for Y2MnZ (Z = Al, Ga, In) in the Hg2CuTi-type structure which well matches with magnetic moments predicted from Slater–Pauling rule. Therefore, the Y2MnZ (Z = Al, Ga, In) in the Hg2CuTi-type structure is predicted to be a candidate for possible spintronics applications. [ABSTRACT FROM AUTHOR]

The electronic, magnetic, and optical properties of PtcoBi half-Heusler compound [001] surfaces and its bulk state have been investigated in the framework of density functional theory using GGa approximation. the half-metallic behaviors of CoBiterm, CoPt-term and PtBi-term decrease with respect to its bulk state. the spin polarization at the Fermi level is 73.2% for the bulk state, and it is -64.4% and -64.1% for the coBi-term and PtBi-term, respectively while less polarization has been observed for the coPt-term. all terminations have given almost similar optical responses to light. Plasmon oscillations for the terminations occur in the range of 12.5 to 14.5 eV (21 to 22 eV) along xx (zz), and it occurs at 23 eV for the bulk state. the refractive index for the bulk and all three terminations is very high in the infrared and visible areas, meaning a very strong metallic trend in these compounds. the phenomenon of super-luminance occurs for the incident light with energy exceeding 5.5 eV for all three terminations, and it occurs in the range of 10 eV for the bulk mode. these terminations show transparent behavior after the energy of 10 eV. [ABSTRACT FROM AUTHOR]

Heusler alloys based on 4d-elements are relatively less explored though they are known to host interesting electronic/magnetic properties useful for future spintronics applications. Here, we report a comparative study of the structural and magnetic properties of FeRuVSi (FRVS) and FeRuVGe (FRVG) using experimental and theoretical tools. Magneto-transport measurements have also been carried out to probe the role of magnetism on their transport behaviour. Room temperature (T) X-ray diffraction data reveals cubic crystal structure (space group No. 216) with B 2 type antisite disorder between Fe and Ru sites in both the alloys. They show ferromagnetic behaviour below the Curie temperature (T C) 84 K for FeRuVSi and 57 K for FeRuVGe respectively. The field dependence of magnetization at low-T shows saturating (nearly saturating) behaviour for FRVS (FRVG). Transport measurements show metallic behaviour with a sharp reduction in the resistivity near T C. Ab-initio calculations predict nearly half metallic behaviour with ∼ 87 % and ∼ 89 % spin polarization for FRVS and FRVG in their ordered states. The inclusion of antisite disorder changes the magnetic configuration, leading to a visible decrease in the magnetic moment and spin polarization. The calculated net moment and the transport properties agree fairly well with those observed experimentally. These results confirm the importance of disorder in determining the intrinsic properties of these alloys. Such combined studies help in the identification of more novel quantum materials suitable for future spintronic applications. ● We present a comparative study of the magnetic, transport, and electronic properties of FeRuVZ (Z = Si, Ge) Heusler alloys. ● Disorder increases the symmetry of the FeRuVSi Heusler alloy to L 2 1 type, higher than that in FeRuVGe. ● The magnetization goes from saturating to nearly saturating behaviour when Si is changed to Ge. ● High spin polarization and nearly half metallic behaviour in the ordered state in both the alloys. [ABSTRACT FROM AUTHOR]

Rhenium-based double perovskite oxides (DPOs) are a particularly fascinating class of materials because of high carrier spin polarization, large magnetic anisotropy energy (MAE), and complex electrical behavior along with high Curie temperature (T C). Herein, we discussed the impact of biaxial ([110]) strain ranging from − 5% to ＋ 5% along the a b -plane on the electronic and magnetic properties of CaCuFeReO 6 (CCFRO) DPO using a b - i n i t o calculations. The unstrained system exhibits a ferrimagnetic (FiM) spin ordering as an energetically stable magnetic ground state due to electron hopping between Fe + 3 /Re + 5 t 2 g and Cu + 2 e g orbitals along with a metallic electronic state. Moreover, [010] (b -axis) is the magnetic easy axis that produces the MAE of 5.36 meV, giving a giant MAE constant of 1.97 × 1 0 7 erg/cm 3. The evaluated partial spin-magnetic moment on the Cu1/Cu2/Fe/Re ion is 0.14/0.44/4.04/ − 0. 64 μ B , where " − " sign on the Re moment means that its spin is antiparallel to the other ions, verifying the FiM ordering in the system. Also, the e g , t 2 g / e g , and t 2 g orbital characteristics of Cu + 2 , Fe + 3 , and Re + 5 ions are visible in the spin-magnetization density iso-surfaces plots, respectively. Using the classical Heisenberg model, the computed T C for the unstrained structure is 576 K, which is quite close to the experimentally reported value of 567 K. In addition, it is shown that the FiM metallic behavior in the motif is robust against biaxial ([110]) strain within the considered range. It has also been revealed that T C increased to 5.73%/3.30% for the considered range of − 5% compressive/＋5% tensile strain due to improved structural distortions. [Display omitted] • A ferrimagnetic (FiM) state is found the energetically stable one. • [010] (b-axis) is the magnetic easy axis having MAE of 5.36 meV, giving a giant MAE constant of 1.97 × 107 erg/cm 3. • T C increased to 5.73%/3.30% for the considered range of −5% compressive/+5% tensile strain. [ABSTRACT FROM AUTHOR]

We employed first-principles calculations to investigate the structural, electronic, and magnetic properties of carbon/boron nitride nanoribbons in different sizes and doping, using twenty-eight zigzag and armchair configurations. We note that the structures present dynamic stability, with formation energies slightly higher than those of the respective undoped nanoribbons. Our electronic calculations revealed that BN-doped armchair carbon nanoribbons exhibit narrow bandgap semiconductor behavior. Most of the zigzag carbon nanoribbons doped with BN exhibited metallic behavior, in addition to exhibiting non-zero spin polarization in these cases. However, carbon-doped boron nitride nanoribbons in both configurations – zigzag and armchair – exhibited wide-gap semiconductor behavior. We also observed that the energy gap in the band structure directly depends on the doping position. The incorporation of boron and nitrogen pairs into the center of the zigzag carbon nanoribbons does not significantly alter the magnetic properties of the nanoribbons. However, when performed at or near the edges, it results in significant changes in spin polarization. Therefore, based on these results, we can consider potential applications of these nanoribbons in electronic devices. • The studied structures exhibit dynamic stability. • Doping-induced semiconductor behavior. • Band structure is directly influenced by doping position. • Doping with boron and nitrogen in nanoribbons has little impact on magnetic properties. [ABSTRACT FROM AUTHOR]

Using spin polarized density functional theory based calculations, combined with ab initio molecular dynamics simulation, we carry out a systematic investigation of the bimetallic Ni13-nAgn nanoclusters, for all compositions. This includes prediction of the geometry, mixing behavior, and electronic properties. Our study reveals a tendency towards the formation of a core-shell like structure, following the rule of putting Ni in a high coordination site and Ag in a low coordination site. Our calculations predict negative mixing energies for the entire composition range, indicating mixing to be favored for the bimetallic small sized Ni-Ag clusters, irrespective of the compositions. The magic composition with the highest stability is found for the NiAg12 alloy cluster. We investigate the microscopic origin of a core-shell like structure with negative mixing energy, in which the Ni-Ag inter-facial interaction is found to play a role. We also study the magnetic properties of the Ni-Ag alloy clusters. The Ni dominated magnetism consists of parallel alignment of Ni moments while the tiny moments on Ag align in anti-parallel to Ni moments. The hybridization with the Ag environment causes reduction of Ni moment. [ABSTRACT FROM AUTHOR]

• Property of multicomponent soft magnetic alloy was predicted by first-principles calculation. • Complex competition exists among Fe, Ni, and Cr in affecting physical properties. • Relatively high contents of Fe and Cr is expected for great electromagnetic performance. • Ni is beneficial to enhancing the system stability of the face-centered cubic structure. • This work give a strategy for accelerated design of multicomponent soft magnetic alloy. Multicomponent alloys (MCAs) exhibit excellent soft magnetic properties and other service performance, and are promising for high-end applications. However, their complicated effects of element mixture and low efficiency in research and development could limit their industrialization. Hence, in this work, first-principles calculation was conducted on the relative formation energy, magnetism and density of states of Fe-Ni-Cr-Si-P-B-C-Nb MCAs for predicting its alloy stability, saturation magnetization (B s) and electric resistivity (ρ). The calculation results mainly present the mixture effects among Fe, Ni and Cr. There is a complex competition among Fe, Ni, and Cr elements in affecting the physical properties of the MCAs. The magnetism of the MCAs is not only determined by composition of magnetic elements but also by the coordination environment around the magnetic atoms. To achieve both high B s and high ρ in the Fe-Ni-Cr-Si-P-B-C-Nb system, proper addition of Fe and Cr may be expected. The optimized MCA has a relatively high B s nearly equal to the Fe-Si-Al system, and exhibits higher ρ and higher spin polarization. This indicates that the proposed MCAs are promising for both power devices and spintronic applications. This work gives a strategy for the property prediction and accelerated design of MCAs by first-principles calculation. It has promising potential to explore other element systems as for high-performance soft magnetic MCAs. [ABSTRACT FROM AUTHOR]

[Display omitted] The quaternary Heusler alloys with composition LiAEFeSb have been studied in this manuscript (AE = Alkaline Earth elements Be, Mg, Ca, Sr and Ba) for their potential applications in spintronics. All the investigations have been performed by employing density functional theory. A systematic comparison of results obtained within local density approximation (LDA) and the generalized gradient approximation (GGA) done. Our calculations reveal that all the studied alloys have lowest energy in type-I arrangement of basis and exhibit interesting electronic and magnetic properties. All the alloys exhibit a stable ferromagnetic ground state. Fixed spin moment calculations rule out existence of any other local magnetic minima. The phonon dispersions show that all the alloys except LiBeFeSb are dynamically stable. Notably, LiSrFeSb and LiBaFeSb exhibit half-metallic electronic band structure and 100 % spin polarization making them suitable choice for promising spintronic applications such as spin filter and detectors. [ABSTRACT FROM AUTHOR]

• The magnetism of LaFe x Ni 1- x O 3 are investigated based on the first principles. • A detail discussion of magnetic performance of FM and AFM in LaFe x Ni 1- x O 3 system. • LaFe x Ni 1- x O 3 undergoes a magnetic transition from FM to AFM when x increases to 0.5. • The magnetic moment of O atom increases with the increase of Fe doping concentration. The effect of different Fe doping concentration (x = 0.125, 0.25, 0.375 and 0.5) on electronic structure and magnetic properties of LaNiO 3 (LNO) have been performed on the spin polarization calculations based on first principles. The calculation results show that with the increase of Fe dopant concentration, LaFe x Ni 1- x O 3 undergoes a magnetic transition from ferromagnetism (FM) to antiferromagnetism (AFM). The net magnetic moments of LaFe 0.125 Ni 0.875 O 3 , LaFe 0.25 Ni 0.75 O 3 , LaFe 0.375 Ni 0.625 O 3 and LaFe 0.5 Ni 0.5 O 3 in the FM ground state are found to be 12.00 µ B /supercell, 16.00 µ B /supercell, 20.06 µ B /supercell and 23.96 µ B /supercell, respectively. In the magnetic configuration of AFM of LaFe x Ni 1- x O 3 (x = 0.125 and 0.375) with the nearest doping position, the asymmetric magnetic structure leads to the symmetry of the spin-ordered AFM network is broken, resulting in the generation of net magnetic moment of -3.06 µ B and 3.87 µ B. The net magnetic moment in LaFe x Ni 1- x O 3 mainly originates from transition metals (TM) Fe, Ni and magnetized O atoms. [ABSTRACT FROM AUTHOR]

• DFT calculations were used to study the magnetic properties of the Fe 2 MnAs alloy. • The influence of point defects on these properties were investigated. • The formation energy, density of states, and magnetic moments, were computed. • The contraction of the lattice enhance the spin polarization of the Fe 2 MnAs alloy. • The defects of Mn As , Mn ↔ As, V As , and V Mn exhibit 100% spin polarization. First-principles calculations within the framework of the density functional theory were conducted using the FP-LAPW method to investigate the electronic and magnetic properties of the Full-Heusler Fe 2 MnAs alloy. The study encompassed the examination of its perfect structure as well as the variation of lattice constants around the ground state. The negative value of the calculated formation energy suggests that the alloy may form spontaneously. From a magnetic perspective, Fe 2 MnAs exhibit a ferromagnetic order. The alloy also shows a high spin-polarization that may be increased, transforming the alloy into a half-metal, with the contraction of the lattice constant. Furthermore, the investigation delved into the effect of point defect formation. The calculated formation energies for vacancies, antisite, and exchange defects suggest the likely occurrence of some of these defects within the Fe 2 MnAs compound. Significantly, certain defects contribute to the spin-polarization of the alloy, effectively rendering it a fully half-metallic material. [ABSTRACT FROM AUTHOR]

• An effect of oxygen vacancy on the electronic and magnetic properties of copper pyrophosphate compound was investigated using DFT calculations. • The vacancy presence reduced the gap width from 2.17 eV to 0.19 eV, changing its character from indirect to direct. • The oxygen vacancies slightly modify the spin polarization of d-orbitals of Cu atoms neighboring the vacancy, resulting in the non-zero total magnetic moment of 0.19 µB/FU. The effect of oxygen vacancies (V O) on the electronic and magnetic properties of copper pyrophosphate dihydrate Cu 2 P 2 O 7 *2H 2 O (CuPPD) semiconductors is studied employing the DFT-based ab initio pseudopotential method. Site preference for vacancy formation on the selected oxygen sublattices is analyzed. Investigations revealed that the V O vacancies led to narrow bands of hybridized Cu-3d and O-2p states within the energy gap of perfect CuPPD semiconductors, significantly reducing the gap width from 2.17 eV to 0.19 eV and changing its character from indirect to direct one. Calculations have shown that the vacancies have no significant influence on the ferrimagnetic structure of CuPPD. The magnetic properties are driven by local magnetic moments of Cu atoms pointed oppositely. The oxygen vacancies slightly modify the spin polarization of d-orbitals of Cu atoms neighboring the vacancy, resulting in the non-zero total magnetic moment of 0.19 µ B /FU (0.0 µ B /FU in perfect CuPPD). The study's main finding, which can be exploited in nanoelectronics, is that the controlled implementation of oxygen vacancies can regulate the energy gap of CuPPD semiconductors. [ABSTRACT FROM AUTHOR]

Density functional theory-based investigation of the electronic, magnetic, and optical characteristics in pure and ytterbium (Yb) doped ZnO has been carried out by the plane-wave pseudopotential technique with generalized gradient approximation. The calculated lattice parameters and band gap of pure ZnO are in good agreement with the experimental results. The energy band gap decreases with increasing Yb concentration. The Fermi level moves upward into the conduction band after doping with Yb, which shows the properties of an n-type semiconductor. New defects were created in the band-gap near the conduction band attributed to the Yb-4f states. The magnetic properties of ZnO were found to be affected by Yb doping; ferromagnetic property was observed for 4.17% Yb due to spin polarization of Yb-4f electrons. The calculated optical properties imply that Yb doped causes a blue shift of the absorption peaks, significantly enhances the absorption of the visible light, and the blue shift of the reflectivity spectrum was observed. Besides, a better transmittance of approximately 88% was observed for 4.17% Yb doped ZnO system. The refractive index and the extinction coefficient were observed to decrease as the Yb dopant concentration increased. As a result, we believe that our findings will be useful in understanding the doping impact in ZnO and will motivate further theoretical research. [ABSTRACT FROM AUTHOR]

The requirement of the continuous reduction of the device size prompts the development of the low-dimensional materials. The structural, electronic, and magnetic properties of CoS2-FeS2 interface thin films are studied by first principles calculations considering spin polarization. The low-dimensional SS-Fe-terminated and SS-SS-terminated CoS2-FeS2 interfacial thin films are half-metallic and therefore are potential materials to be applied in spintronics. Both the partial density of states and Bader charge states of atoms are more affected by the surface effect than by the interface effect for all the interfacial thin films. The magnetic moment of the CoS2-FeS2 interface thin films is mainly distributed on Co atoms on the CoS2 side, and the changes of magnetic moment of the atoms near the surface are more obvious than those near the interface. The magnetic charge density of Fe atoms in the metallic interfacial thin films is more obvious than that in the half-metallic interface films. The individual CoS2 (FeS2) film and the SiO2 substrate affect the property of the corresponding CoS2-FeS2 interfacial thin film. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the structural, the electronic and the magnetic properties of the equiatomic quaternary Heusler alloy CoRuMnGe using the first-principle calculations. In fact, we apply the DFT method under Quantum Espresso package. For this purpose, we have examined the structural properties in order to determine the stability of the three configurations of this alloy: type I, type II and type III. Our calculations confirmed that the configuration of type I is the most stable one for the equiatomic quaternary Heusler alloy CoRuMnGe. Consequently, we have studied the electronic, magnetic properties and exchange coupling interactions only for the stable configuration. Also, we have illustrated the nearly half metallic behavior of this alloy, and deduced the rule Slater Pauling. On the other hand, following the mean-field approximation (MFA), we computed the Curie temperature value T C MFA = 446.53 K for the studied compound. [ABSTRACT FROM AUTHOR]

In order to unveil the effect of interstitial V‐doped SrO compound an ab initio calculation is carried out within the FP‐LAPW+lo method. To do this task, the modified GGA‐PBEsol potential is employed to predict structural, electronic, and magnetic properties of two alloys, SrV0.125O and SrV0.25O. The lattice parameters are found in good agreement with the existing theoretical and experimental data. The calculation shows both SrV0.125O and SrV0.25O alloys are energetically and mechanically stable. The interstitial doping changes the ionic nature of the SrO compound in half‐metallic ferromagnetic comportment one, with a spin polarization of 100% at the Fermi level. Magnetic properties are also predicted. After a deep analysis, the low magnetic moment is attributed to the strong hybridization of O‐p‐V‐d orbitals. [ABSTRACT FROM AUTHOR]

With the intention to reveal the effect of the substitution, Ti-doped InSb alloy, we accomplished a first-principles prediction within the FPLAPW+lo method. We used GGA-PBEsol scheme attached with the improved TB-mBJ approach to predict structural, electronic, and magnetic properties of In1-xTixSb with concentration x = 0, 0.125, 0.25, 0.50, 0.75, 0.875, and 1. Our lattice parameters are found in favorable agreement with the available theoretical and experimental data. The calculation shows that all structures are energetically stable. The substitutional doping transforms the ionic character of the InSb compound in half-metallic ferromagnetic comportment for concentration x = 0, 0.125, 0.25, and 0.50, with a spin polarization of 100% at the Fermi level, and metallic nature for In0.25Ti0.75Sb and In0.125Ti0.875Sb. The total magnetic moments are also estimated at about 1 μB. In0.875Ti0.125Sb, In0.75Ti0.25Sb, and In0.50Ti0.50Sb have half-metallic ferromagnets comportment and they can be upcoming applicants for spintronics applications. [ABSTRACT FROM AUTHOR]